Low-specificity L-threonine aldolase

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Low-specificity L-threonine aldolase
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EC no. 4.1.2.48
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Low-specificity L-threonine aldolase (EC 4.1.2.48, LtaE) is an enzyme with systematic name L-threonine/L-allo-threonine acetaldehyde-lyase (glycine-forming). [1] [2] [3] [4] [5] This enzyme catalyses the following chemical reaction

(1) L-threonine glycine + acetaldehyde
(2) L-allothreonine glycine + acetaldehyde

This enzyme requires pyridoxal phosphate.

Related Research Articles

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L-allo-threonine aldolase is an enzyme catalyzing the conversion between L-allothreonine on one side and glycine plus acetaldehyde on another side. Artificial disabling (knockout) of this enzyme in wild bacteria has no significant effect. However such disabling suppresses the growth of mutants that already lack other enzyme, serine hydroxymethyltransferase. Hence L-allo-threonine aldolase provides the alternative pathway for cellular glycine when serine hydroxymethyltransferase is inert. E.coli L-allo-threonine aldolase is a highly termostable enzyme, this can be used for purification.

Phosphoserine transaminase is an enzyme with systematic name O-phospho-L-serine:2-oxoglutarate aminotransferase. This enzyme catalyses the following chemical reaction

Glutathione hydrolase (EC 3.4.19.13, glutathionase, GGT, gamma-glutamyltranspeptidase) is an enzyme. This enzyme catalyses the following chemical reaction

D-threonine aldolase is an enzyme with systematic name D-threonine acetaldehyde-lyase (glycine-forming). This enzyme catalyses the following chemical reaction

3-hydroxy-D-aspartate aldolase is an enzyme with systematic name 3-hydroxy-D-aspartate glyoxylate-lyase (glycine-forming). This enzyme catalyses the following chemical reaction

Glycine C-acetyltransferase is a protein that in humans is encoded by the GCAT gene.

References

  1. Yamada H, Kumagai H, Nagate T, Yoshida H (April 1970). "Crystalline threonine aldolase from Candida humicola". Biochemical and Biophysical Research Communications. 39 (1): 53–8. doi:10.1016/0006-291x(70)90756-4. PMID   5438301.
  2. Kumagai H, Nagate T, Yoshida H, Yamada H (March 1972). "Threonine aldolase from Candida humicola. II. Purification, crystallization and properties". Biochimica et Biophysica Acta (BBA) - Enzymology. 258 (3): 779–90. doi:10.1016/0005-2744(72)90179-9. PMID   5017702.
  3. Liu JQ, Nagata S, Dairi T, Misono H, Shimizu S, Yamada H (April 1997). "The GLY1 gene of Saccharomyces cerevisiae encodes a low-specific L-threonine aldolase that catalyzes cleavage of L-allo-threonine and L-threonine to glycine--expression of the gene in Escherichia coli and purification and characterization of the enzyme". European Journal of Biochemistry. 245 (2): 289–93. doi: 10.1111/j.1432-1033.1997.00289.x . PMID   9151955.
  4. Liu JQ, Dairi T, Itoh N, Kataoka M, Shimizu S, Yamada H (July 1998). "Gene cloning, biochemical characterization and physiological role of a thermostable low-specificity L-threonine aldolase from Escherichia coli". European Journal of Biochemistry. 255 (1): 220–6. doi: 10.1046/j.1432-1327.1998.2550220.x . PMID   9692922.
  5. Kim J, Kershner JP, Novikov Y, Shoemaker RK, Copley SD (November 2010). "Three serendipitous pathways in E. coli can bypass a block in pyridoxal-5'-phosphate synthesis". Molecular Systems Biology. 6: 436. doi:10.1038/msb.2010.88. PMC   3010111 . PMID   21119630.